Flask



FIG. 1 is an exploded perspective view of a flask showing the present invention;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a side elevation view thereof, the opposing side elevation view being identical;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a cross-section view taken along the line 6-6 in FIGS. 4 & 5. 

CLAIM The ornamental design for a flask, as shown and described. 